In a medium saucepan combine water, onion, garlic, oregano, chicken bouillon granules, lemon peel or juice, and pepper. Bring to boiling. Stir in rice; reduce heat. Cover and simmer for 10 minutes.
Stir in spinach. Cover and cook for 5 to 10 minutes more or until rice is tender and liquid is absorbed. Stir lightly with a fork before serving. Garnish with lemon peel strips, if desired. Makes 4 side-dish servings.